That would be a pretty cool glitch I might just check it out.
It does sound like the weapon duplication trick. I know that one is true. I made a excalibur for every character.
Are you sure you just didn't get those two mixed up? For your question if you figured out how to do the glitch couldn't you just try it for every class? I have no idea. I didn't even know that there was a glitch like that.